Steam irons have a heated soleplate that contacts a garment during ironing. A steam engine in the soleplate is supplied with water under the force of gravity to produce steam that exits the soleplate through a steam vent or a number of steam vents towards a garment during ironing to improve ironing performance.
It is understood that ironing performance is further improved when the steam exiting the steam vent(s) is at a relatively high pressure. However, steam pressure and quantity of steam is limited by the amount of water that can be supplied to the soleplate under gravitational force. The steam generated in the steam engine also creates a back pressure which opposes the flow of water into the steam generator, resulting in reduced steam production.
It is known to increase the quantity and pressure of the steam by generating steam in a boiler outside the iron and supplying it to the iron through a flexible hose, or by using a pump to supply water under pressure into the steam engine. However, these solutions are not always appropriate or desirable and cannot be used if, for example, the iron is a cordless version that does not have a direct power supply or steam conduit connected to the iron.
JP H02 305600 describes delivering a force of water high enough to allow the generation of high power steam by providing a pressurizing pump which pressurizes a space in a water tank when an iron body is mounted in an iron stand. When, after water is poured in a water tank, the water tank is mounted to an iron body and is set on an iron stand, a source feed circuit is actuated to start energization to a heater. In this case, a pressurizing pump is also actuated to push up the ball valve of a suction port and air is fed in the water tank to effect pressurization. When, after the heater is heated, the use of the iron is started, a space at the upper interior of the water tank forms an air reservoir and a pressure higher than an atmospheric pressure is generated in the space and therefore, a pressure is exerted on water in the water tank. When, with this state, a push button is depressed, a water passage on-off valve is opened, water is pushed out with a force in a gasifying chamber through a nozzle through the action of the pressure in the water tank. The water instantaneously produces steam and is injected as high power steam through an iron base.
DE3544506 describes the formation of a light currentless and cordless storage-type dry and steam-regulating iron with an open handle, which is designed with a storage fluid of high capacity and low specific gravity and with a store and pre-stored push-in storage elements and a steam-superheating generator and hot-water pressure vessel which can be lifted off automatically, and a tiltably arranged hot-water pressure spray nozzle with a tilting inflow shut-off valve and, in addition, with automatic vacuum-suction and pressurized-water feed.
US2002/029498 describes a rapid cool iron having a body and a low specific heat sole plate having an element bonded to or formed upon a top surface, said body and said sole plate being separated by an air gap to allow for the free flow of air over said top surface of said sole plate. Also described is a fan to more rapidly cool the sole plate through forced convection. Also described is a controller that is configured to only apply power when the rapid cool iron is in a horizontal orientation. Also described is a steam generator which may be independent from or integrated with the sole plate, an external water reservoir/stand which includes a water filter, an ergonomically designed tilt handle with integrated controls and a grip sensor, and a forward facing light to illuminate the material being ironed.
DE19524333 describes a steam iron having an electronic control system which detects which of the separate water consumption units is switched on through the timing of pressure changes in the pressure store. The electronic control switches the pump off after a preset maximum time if a given water consumption unit, the additional steaming chamber, is switched on.
US2008/229628 describes a steam ironing device comprising a steam generator for heating water to steam, a steam outlet for letting out a burst of steam from the steam generator, a device for supplying water to the steam generator, a hose connecting the water supplying device to the steam generator, and a controller which is adapted to operating the water supplying device during a period of time in a situation in which there is hardly any need or no need at all of a supply of steam in an ironing process, while keeping the steam outlet closed. In this way, a reserve amount of steam is generated, which is stored in an internal space of the steam generator, and, as the occasion arises, inside at least a portion of the hose. When a burst of steam is required, the reserve amount of steam is released through the steam outlet.
U.S. Pat. No. 1,697,224 A describes an electric iron having incorporated therein manually controlled means by which steam can be generated as desired and applied to the cloth or garment during the normal pressing operation of the sad iron, whereby a combined steaming and pressing of the cloth can be effected conveniently and expeditiously and to the elimination of the old method of employing a wet cloth for dampening.